The present invention relates to smokestack emission control devices and especially to such a device for mounting directly on top of a smokestack and forcing the emissions to pass through a liquid bath.
In the past there have been a great variety of emission control devices for use in connection with smokestacks or other emission stacks. The most common type of emission control device for smokestacks is probably scrubberS, which typically captures the emissionS from the exhaust and passes it through a separate building where water is continuously sprayed from the top while the emissions enter from the bottom and pass through the sprayed water. The droplets of water capture solids in the gas and will hydrolyze components in the gas for removing harmful chemical components from the emissions. Another commonly used but more expensive technique involves electrostatic precipitation which places a charged field in or near the smokestack and passes the gases through an electrically charged screen of one polarity first and then through a second electrically charged screen of a second polarity. A charge is placed on fine solids in the gases which are then attracted to the second screen and removed from the gases. The attracted particles can be burned on the second screen or accumulated into larger particles, where they fall back into the smokestack or they can be otherwise removed from the screen.
The present invention relates to a smokestack emissions control device which is attached directly to the smokestack and which passes all of the emission gases directly through a liquid bath which can be formulated for the particular emissions. The smokestack would typically support the present invention because of its light weight. Since only a small tank of liquid is maintained in the stack while the main reservoir circulates the liquid while separating solids and chemicals from the liquid from a separator unit at the base of the stack. It has, however, in the past been taught to circulate combustion gases, and the like, directly through liquid baths, including liquid baths having other chemicals therein. In the prior Greenberg U.S. Pat. No. 3,647,358, components of the combustion gas are oxidized by passing them through a molten salt bath in one embodiment and impinging gases against the liquid surface in other embodiments. A second Greenberg patent, U.S. Pat. No. 4,173,190, uses an incinerator having a coiled tubing in a bath of molten salt and includes passing the exhaust gases through the molten salt bath. In the patent to Cremo, U.S. Pat. No. 4,257,792, a steam pressure smoke eliminator is mounted directly to tall smokestacks and is adapted to generate steam for cleaning exhaust gases. In the Pweblo patent, U.S. Pat. No. 4,437,866, a pollution harness is used for removing flue gases from the atmosphere by mixing smoke with water. The Scott patent, U.S. Pat. No. 4,231,765, discloses an air cleaning apparatus which directs air through upper and lower water curtains to act as a small scrubber in a small reservoir. Recirculating water is periodically drained and refilled. The DiProspero patent, U.S. Pat. No. 3,757,708, shows flue gases directed through a fluid tank while the Blair patent, U.S. Pat. No. 3,850,118, shows an incinerator in which the firebox is exhausted through a water tank. The aim of the present invention is to produce a lightweight smokestack emission control system which can be mounted directly onto existing smokestacks without putting undue weight on the stacks, and which can cool and remove pollutants from the exhaust gases by passing the gases and solids in the gases through a liquid bath formulated for the particular emissions and providing constant recirculation and cleaning of the liquid at a remote location.